Alliant Energy : Settlement Parameters - Iowa Rate Review

Published: 2024-06-20 18:33:08 ET LNT

Alliant Energy Corporation

Settlement Parameters - Iowa Rate Review

June 20, 2024

Safe Harbor

This presentation contains statements that may be considered forward looking statements. Actual results could differ materially because the realization of those results is subject to many uncertainties, including: regulatory action on non-unanimous settlement agreement by the Iowa Utilities Board; and other factors discussed in more detail in Alliant Energy Corporation's (Alliant Energy) SEC filings. Alliant Energy cannot provide any assurance that the assumptions used in the forward-looking statements or otherwise are accurate or will prove to be correct. All forward-looking statements included in this presentation are based upon information presently available, and Alliant Energy assumes no obligation to update any forward-looking statements.

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Settling parties align to advance economic development growth and provide customer base rate stability

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Iowa non-unanimous rate review settlement

Docket RPU-2023-0002

Summary of non-unanimous electric and gas rate review settlement agreement:

Settling Parties

Office of Consumer Advocate (OCA), a division of the Department of Justice and

Iowa Business Energy Coalition (IBEC)

Increase in retail electric revenue requirements (2-year phase-inthrough a rider)

$185 million

Increase in retail gas revenue requirements (single year implementation)

$10 million

Authorized return on equity for non-advance ratemaking assets

9.65%

Authorized regulatory equity level (with a band of +/-0.25 for purpose of earnings sharing)

51.0%

Electric rate base

$7,279 million

Gas rate base

$630 million

5-year base rate moratorium and earnings sharing mechanism; retain tax benefits and energy margins for new investments

Support for individual customer rate rider (Rider ICR) tariff revision

No return on the remaining net book value of retired Lansing Generating Station

Subject to approval by the Iowa Utilities Board

The information above is merely a summary of certain key terms of the non-unanimous settlement and is qualified by reference to the full text of the settlement, which can be found at the following link: https://efs.iowa.gov/filing/4685657. Any material non-cash regulatory charges related to the Lansing Generating Station will be provided in a Form 8-K to be filed with the Securities and Exchange Commission.

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Disclaimer

Alliant Energy Corporation published this content on 20 June 2024 and is solely responsible for the information contained therein. Distributed by Public, unedited and unaltered, on 20 June 2024 22:32:09 UTC.